Facebook’s COO incited a new conversation on feminism in the workplace with her March 2013 book, Lean In: Women, Work, and the Will to Lead. The manifesto sold nearly 150,000 copies in its first week, and it has held the top nonfiction spot on best-seller lists since. But Sandberg’s biggest success of the year may have happened right in Menlo Park. After adding ads to its mobile News Feed, Facebook earned more U.S. mobile revenue than any other publisher in 2012, with an 18.4 percent share of the entire market. The April release of Home, the new Facebook phone, will reportedly allow companies to send advertising directly to users’ smartphones even if the home screen is locked. 2013 spotlight: One year after Facebook’s initial public offering, the company’s stock is down roughly 30 percent.